High-resolution and large-dynamic-range temperature sensor using fiber Bragg grating Fabry-Pérot cavity

A high-resolution and large-dynamic-range temperature sensor adopting a pair of fiber Bragg grating as Fabry–Pérot cavity (FBG-FP) and laser frequency dither locking method is proposed and experimentally demonstrated. This sensor exhibits a temperature resolution of 7×10 −4 °C and a dynamic range of ∼46 °C. It is especially useful for applications where very small temperature changes need to be detected, such as deep ocean temperature measurement.